A stock price is currently $40. It is known that at the end of six months, it will be either $45 or $35. The risk-free rate is 5% per year.

(1) Use no-arbitrage method to calculate the value of a six-month European call option on the stock with an exercise price of $40.

(2) Use risk-neutral valuation method to calculate the value of a six month European put option on the stock with an exercise price of $43.